arrow on piston
got in some kits today with top end removed
put 4 together so far & found 2 with piston arrow pointing forward & 2 with arrow pointing back (with locating pins on intake side)
all from same supplier, all seem same as far as other h/w goes, all machined cranks
the point: never look at the arrow (if it has one)
Sometimes I sets and thinks, sometimes I jes sets.